There are several medical conditions which can benefit from implantation into a patient of a filler material, an embolization or other device, whether temporary or permanent. Examples include the closure of blood vessels or other lumens so as to occlude these. One condition for which such procedures can be particularly useful is in the treatment of aneurysms, where a part of a vessel wall weakens and then expands outwardly to create an enlarged zone of the vessel, often having the form of a sac. This vessel expansion occurs as a result of blood pressure and tends to continue due to further and progressive weakening of the vessel wall. If left untreated, persistent pressure from the blood flow on the weakened wall tissue can lead to eventual rupture of the vessel wall and consequential haemorrhaging. Treatments for aneurysms have therefore focused on reducing the pressure on the weakened vessel wall, for instance by diverting blood flow or by isolating the weakened vessel wall for instance by means of a stent graft. Another treatment method involves filling the aneurysm sac with a filler material which stops the flow of blood into the sac and therefore stops or substantially reduces the pressure on the weakened walls. The filler may be an embolization coil, which will cause blood therearound to clot and thus close the sac and provide a protective barrier to prevent vessel rupture. In other instances, the aneurysm may be filled with a biocompatible material, such as a hydrogel or a polysaccharide fibre, which may be of a biodegradable nature. A biodegradable filler performs the same function as an embolization coil, that is to fill the aneurysm sac and provide pressure protection to the weakened vessel walls, with the additional advantage of allowing remodelling of the vessel wall over time. Moreover, biodegradation of the filler will ensure that no foreign matter remains in the patient's vessel after conclusion of the treatment.
Such fillers and coils can also be used to close off a vessel or other lumen in a patient.
The process of introducing such a filler or coil into a patient can take time, particularly given that this is often carried out remotely from the aneurysm by an endoluminal procedure.
Examples of prior art devices and methods can, for instance, be found in U.S. Pat. No. 6,312,421, US-2006/0147483, U.S. Pat. No. 6,589,199, U.S. Pat. No. 6,440,098.